Method of making sulfuric acid.



No. 729,643. PATENTED JUNE 2, 1903.

M. NEUMANN. METHOD OF MAKING SULFURIG ACID.

APPLICATION TILED OUT. 10, 1902.

' 3 SHEBTS-SHEBT 1.

N0 MODEL.

No. 729,643. PATEN'I'ED JUNE 2, 190a.

M. NEUMANN.

METHOD OF MAKING SULFURIG ACID.

APPLIOATIOH FILED OUT. 10, 1902.

no MODEL. a snnmssnnn'r z.

(if (45: W XM v I I No. 729,643. PATEN TED JUNE-2, 1903. M. NEUMANN.

METHOD OF MAKINGSULFURIO ACID.

APPLICATION FILED our. 10, 1902. no MODEL. a SHEETS-SHEET 3.

No. 729,643-. l

UNITED STATES IPatented une 190G.

PATENT owes.

MAX NEUMANN, on HAM B ORN GE RMANY, Assrenon TO FRANZ MEYER,

' OFHAMBORN," GERMANY.

M ono F-MAJ NG.i j F' Rijo AC sracrrrcnrromi forming part of Letters ratemnd. raaeas, dated. June 2, 1903. Application filedOctober 10, 1902. SeriaI NO- 126,72lf lNo specimens.)

Making Sulfuric Acid; and I do hereby de-' clare the following to be a full, clear, and exact description of the invention; such as will enable others skilled in the art to which it.

utilize these considerations by providing a appertains to make and'use'the same.

In the chamber processfor the manufac-- ture of sulfuric acid. the reaction equations, which are also verified. by the actual results obtained, call for the formation of w -moiecules of-II SO by means or two'molecules of NO, which latter are potentially present in reaction and form three molecules of H280 Therefore the same quantity of N0 inthe same space has fifty per cent. greater efficiency in the Glover process. j

In the chamber process it is merely necessary thatcare be taken to remove the excess of heat of reaction incident to the intimate commingling of the gases. In the Glover process, on the other hand, in order to denitrate.-. 6., to decompose the nitroxylsulfuric acid by means of S0 and H O-a certain high initialtemperature must be employed, such temperature, in fact, prevailing in the lower part of the ordinary Glover tower. .Because of the reduction of the N20 to NO the opera; tion involves an endothermic reaction -i. a, it proceeds with the absorption of a part of the heat of formation of the H530 which absorbed heat is subsequently restored in the next succeeding step of the process, (the formation of the nitroxylsulfuric acid,) together with theheat of reaction of said succeeding step, so that in this latter step or phase of the process much'more energetic cooling is required than in working in accordance with the chamber-process. Inasmuch, therefore, as heat and cold must act successively, the process can only proceed to advantage in sharpl -defined successive phases-2'. 6., only when hot and cold zones alternate with each other. Not only does the same quantity of NO develop from the Glover reaction equation alone in the same space, an increased eificiency of fifty per cent. in comparison to the chamber process, but it is also to be noted that in the Glover process the efficiency is still further very considerably increased, because of the well-known fact that the Glover process proceeds much more rapidly than the relatively slow-working-chamber process.

. The purpose oft-he present invention is to succession of hot and cold zones separated in time and space from each other aside from the ordinary single Glover tower heretofore employed and especially to employ a num ber of Glover towers in the general operation,

:so that the extraordinarily complete and effective Glover process may be made available to as great an extent as possible in the production of sulfuric acid.

The temperature requiredfor the decomposition of the nitroxylsulfuric acid rises progressively as the gases become poorer in 80,. Therefore the method is of course commercially advantageous only as long as the excess of SO over 0 is relatively great,'so that the necessary temperature maybe obtained with the cheap materials available in practice.

The apparatus maybe considerably varied. For instance, it may consist of fines, towers, and the like interposed between Glover tower and lead-chambers or connected to the Glover tower alone, care being taken to establish alternate hot and coldzones in said interposed fines or towers by the introduction of heating. and cooling devices. Inasmuch as the, said fines and towers are traversed in the portions of the apparatus being exhibited as broken away. Fig. 2 represents a top plan view thereof. Figs. 3, 4, and 5 represent sectional details.

Similar letters of reference indicate similar parts throughout the several views.

Referring to the drawings, A, B, and G represent three towers of the Glover type, and D E represent two heating-chambers having an outer jacket of heat-insulating material to protect them as far as possible against heat radiation and provided at its lower or inferior part with an inner jacket of lead. The chambers D E, as shown more fully in Figs. 3, 4, and 5, contain a series of tubes or fines a, of earthenware, lava, or other refractory acid-resisting material. These chambers receive from the supply-flue F the hot gases from a pyrites furnace or furnaces, which in their passage through the chambers D E heat externally the tubes contained therein. After passing through the chambers D E the furnace-gases having parted with a portion of their heat enter the lower portion of the Glover tower A at a temperature of but 160 to 1.90 eentigrade, which is more than sufficient to effect complete denitration. The gases, as usual, pass upwardly through the Glover tower A, meeting 011 theirway upward the customary downwardly-trickling mixture of nitrose and dilute acid. Asin every Glover tower a complete Glover zone, with alternate upward and downward movement of the reagents, is established-to wit, first, an upper zone for the formation of nitroxyl, which I have indicated in the drawings by the letters 0 Z, because of the oxidizing action taking place therein, and, second, a lower or reducing zone for denitration, (indicated by the letters R Z.)

Up to a certain limit the colder the oxidizing zone the more N0 molecules are compelled .each time to move downward to be combined into nitroxylsulfuric acid. For the obtaining and maintenance of the ideal low temperature cooling-pipesf, of acid-resisting material, are inserted in the upper part of the towers, around which pipes a circulation of cold air or cold liquid is maintained.

The condensation of steam in the upper part of the tower (and the consequent premature beginning of denitration and accompanying diminution of the active reactionspace) is not to be feared, for the reason that at the temperatures of admission of 200 eentigrade and thereunder prevailing in my apparatus much less steam is present than at the admission-temperatures of 350 to 450 eentigrade of the ordinary Glover tower and because sprinkling acid of corresponding strength (57 to 58 Baum) may be selected, so that any precipitated or condensed water would be used up at once to bind the new H SO The unconverted gases (NO,SO ,O)

- and a small quantity of H 0 escape at the upper part of the tower A and pass downward through the pipe g. On their downward course they are subjected to mixing and cooling, for which latter purpose the pipe 9 may be conveniently provided with a coolingjacket g, through which cold water from a pipe h may be continuously passed whereupon nitroxylsulfuric acid will be formed.

Should there be too small a quantity of water during the simple onward travel of the gas mixture and with the advantage that the fifty per cent. greater efficiency of the Glover equation is obtained.

A portion. of the acid formed in D collects on the bottom of that chamber and may be drawn off through the opening 70. On account of its high concentration it is high in nitrose-11 e., it must pass through the Glover tower for denitration, in this manner bring ing the sprinkling acid up to the desired strength of 57 to 58 Baum.

From D the gas mixture heated up to from 170 to 200 eentigrade enters through the pipe m. The lower portion of the Glover tower B issues from the top of said tower into the downtake g and thence into the preheater E, which latter corresponds in all respects with the like preheater D. From preheater E it passes by pipe 19 into the lower part of the Glover tower O and thence through the down takeg into the first of the series of Lunge- Rohrm ann towers F GH and Gay-Lussac tower 1, escaping finally through the exhaust-blower K. It will of course be understood that the towers B and C and the downtakes g and g are provided with like cooling devices-as the tower A and downtake g and that the platetowers may be replaced by lead-chambers. By thus dividing up and utilizing at suitable places the heat of the gases from the pyrites furnaces and by the expedient of alternately cooling said gases it has been made possible to conduct the gas mixture through three complete Glover towers each having one pair of oxidizing and reducing zones with up-anddown movement of the agents and in addition thereto two further pairs of oxidizing and reducing zones with simple onward travel of the gas. It is self-evident that it is also possible to substitute for the heat of the pyrites-furnaee gases direct heating or heating by fire-tubes from any furnace-stack flue, although in that event, with the danger that should any of the heating-tubes burst, a portion of the Glover gases would be drawn Therefore in this way a second pair of oxidizing and reducing zonesis established ICS through the burst tube or tubes and pass off into the stack. Therefore for absolute security it is desirable in the present arrangement to make use of the heat of the pyritesfurnace gases, inasmuch as thereby all gas losses are excluded and for the further reason that it is more convenient and more economical and likewise because it becomes impossible to overheat the Glover towers, and thus prejudicially effect the Glover filling. After traversing the three Glover towers and the two preheaters the gas mixture becomes relatively so poor in S0; that the temperatures thereafter necessary for transformation according to the Glover equation cannot be obtained. It is therefore preferable to conduct the remaining gas into a lead chamber or chambers and work it up there or (if it is desiredto dispense with a lead-chamber) in lieu thereof to employ a few Lunge-Rohrmann plate-towers.

Having thus described my invention, what I claim is- 1. The method of making sulfuric acid, consisting in conducting the acid-producing gases through a plurality of Glover towers, and through alternate heating and cooling zones intermediate of said towers; substantially as described.

2. The method of making sulfuric acid,

consisting in conducting the acid-producing gases through a plurality of Glover towers,

and through'alternate heating and cooling 4. The method of making sulfuric acid,

consisting in passing kiln-gases through a plurality of Glover towers, and through alternate heating and cooling zones intermediate of said towers, the heating zones deriving their heat from the waste heat of the kiln-gases and in inverse order from the last to the first of the series; substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

MAX NEUMANN.

Witnesses HENRY HASPER, WALDEMAR HAUPT. 

